Tracing magnetism and pairing in FeTe-based systems

In order to examine the interplay between magnetism and superconductivity, we monitor the non- superconducting chalcogenide FeTe and follow its transitions under insertion of oxygen, doping with Se and vacancies of Fe using spin-polarized band structure methods (LSDA with GGA) starting from the collinear and bicollinear magnetic arrangements. We use a supercell of Fe8Te8 as our starting point so that it can capture local changes in magnetic moments. The calculated values of magnetic moments agree well with available experimental data while oxygen insertions lead to significant changes in the bicollinear or collinear magnetic moments. The total energies of these systems indicate that the collinear-derived structure is the more favorable one prior to a possible superconducting transition. Using a 8-site Betts-cluster-based lattice and the Hubbard model, we show why this structure favors electron or hole pairing and provides clues to a common understanding of charge and spin pairing in the cuprates, pnictides and chalcogenides

'Choosing shoes': a preliminary study into the challenges facing clinicians in assessing footwear for rheumatoid patients

Background: Footwear has been accepted as a therapeutic intervention for the foot affected by rheumatoid arthritis (RA). Evidence relating to the objective assessment of footwear in patients with RA is limited. The aims of this study were to identify current footwear styles, footwear characteristics, and factors that influence footwear choice experienced by patients with RA. Methods: Eighty patients with RA were recruited from rheumatology clinics during the summer months. Clinical characteristics, global function, and foot impairment and disability measures were recorded. Current footwear, footwear characteristics and the factors associated with choice of footwear were identified. Suitability of footwear was recorded using pre-determined criteria for assessing footwear type, based on a previous study of foot pain. Results: The patients had longstanding RA with moderate-to severe disability and impairment. The foot and ankle assessment demonstrated a low-arch profile with both forefoot and rearfoot structural deformities. Over 50% of shoes worn by patients were opentype footwear. More than 70% of patients’ footwear was defined as being poor. Poor footwear characteristics such as heel rigidity and sole hardness were observed. Patients reported comfort (17%) and fit (14%) as important factors in choosing their own footwear. Only five percent (5%) of patients wore therapeutic footwear. Conclusions: The majority of patients with RA wear footwear that has been previously described as poor. Future work needs to aim to define and justify the specific features of footwear that may be of benefit to foot health for people with RA

Patterns of primary care and mortality among patients with schizophrenia or diabetes: a cluster analysis approach to the retrospective study of healthcare utilization

Abstract Background Patients with schizophrenia have difficulty managing their medical healthcare needs, possibly resulting in delayed treatment and poor outcomes. We analyzed whether patients reduced primary care use over time, differentially by diagnosis with schizophrenia, diabetes, or both schizophrenia and diabetes. We also assessed whether such patterns of primary care use were a significant predictor of mortality over a 4-year period. Methods The Veterans Healthcare Administration (VA) is the largest integrated healthcare system in the United States. Administrative extracts of the VA's all-electronic medical records were studied. Patients over age 50 and diagnosed with schizophrenia in 2002 were age-matched 1:4 to diabetes patients. All patients were followed through 2005. Cluster analysis explored trajectories of primary care use. Proportional hazards regression modelled the impact of these primary care utilization trajectories on survival, controlling for demographic and clinical covariates. Results Patients comprised three diagnostic groups: diabetes only (n = 188,332), schizophrenia only (n = 40,109), and schizophrenia with diabetes (Scz-DM, n = 13,025). Cluster analysis revealed four distinct trajectories of primary care use: consistent over time, increasing over time, high and decreasing, low and decreasing. Patients with schizophrenia only were likely to have low-decreasing use (73% schizophrenia-only vs 54% Scz-DM vs 52% diabetes). Increasing use was least common among schizophrenia patients (4% vs 8% Scz-DM vs 7% diabetes) and was associated with improved survival. Low-decreasing primary care, compared to consistent use, was associated with shorter survival controlling for demographics and case-mix. The observational study was limited by reliance on administrative data. Conclusion Regular primary care and high levels of primary care were associated with better survival for patients with chronic illness, whether psychiatric or medical. For schizophrenia patients, with or without comorbid diabetes, primary care offers a survival benefit, suggesting that innovations in treatment retention targeting at-risk groups can offer significant promise of improving outcomes.http://deepblue.lib.umich.edu/bitstream/2027.42/78274/1/1472-6963-9-127.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78274/2/1472-6963-9-127.pdfPeer Reviewe

Van der Waals epitaxy between the highly lattice mismatched Cu-doped FeSe and Bi₂Te₃

We present a structural and density functional theory study of FexCu1−xSe within the three-dimensional topological insulator Bi2Te3. The FexCu1−xSe inclusions are single-crystalline and epitaxially oriented with respect to the Bi2Te3 thin film. Aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy show an atomically sharp FeICu1−xSe/Bi2Te3 interface. The FexCu1−xSe/Bi2Te3 interface is determined by Se–Te bonds and no misfit dislocations are observed, despite the different lattice symmetries and large lattice mismatch of ∼19%. First-principle calculations show that the large strain at the FexCu1−xSe/Bi2Te3 interface can be accommodated by van der Waals-like bonding between Se and Te atoms

Evidence-based obstetrics in four hospitals in China: An observational study to explore clinical practice, women's preferences and provider's views

BACKGROUND: Evidence-based obstetric care is widely promoted in developing countries, but the success of implementation is not known. Using selected childbirth care procedures in four hospitals in Shanghai, we compared practice against evidence-based information, and explored user and provider views about each procedure. METHODS: Observational study. Using the Cochrane Library, we identified six procedures that should be avoided as routine and two that should be encouraged. Procedure rate determined by exit interviews with women, verified using hospital notes. Views of women and providers explored with in depth interviews. The study sites were three hospitals in Shanghai and one in neighbouring province of Jiangsu. 150 women at each centre for procedure rate, and 48 in-depth interviews with women and providers. RESULTS: Vaginal births were 50% (303/599) of the total. Of the six practices where evidence suggests they should be avoided as routine, three were performed with rates above 70%: pubic shaving (3 hospitals), rectal examination (3 hospitals), and episiotomy (3 hospitals). Most women delivered lying down, pain relief was rarely given, and only in the urban district hospital did women routinely have a companion. Most women wanted support or companionship during labour and to be given pain relief; but current practice is insufficient to meet women's needs. CONCLUSION: Obstetric practice is not following best available evidence in the hospitals studied. There is a need to adjust hospital policy to support the use of interventions proven to be of benefit to women during childbirth, and develop approaches that ensure clinical practice changes

Common and Unique Contributions of Decorin-Binding Proteins A and B to the Overall Virulence of Borrelia burgdorferi

As an extracellular bacterium, the Lyme disease spirochete Borrelia burgdorferi resides primarily in the extracellular matrix and connective tissues and between host cells during mammalian infection, where decorin and glycosaminoglycans are abundantly found, so its interactions with these host ligands potentially affect various aspects of infection. Decorin-binding proteins (Dbps) A and B, encoded by a 2-gene operon, are outer surface lipoproteins with similar molecular weights and share approximately 40% identity, and both bind decorin and glycosaminoglycans. To investigate how DbpA and DbpB contribute differently to the overall virulence of B. burgdorferi, a dbpAB mutant was modified to overproduce the adhesins. Overproduction of either DbpA or DbpB resulted in restoration of the infectivity of the mutant to the control level, measured by 50% infectious dose (ID50), indicating that the two virulence factors are interchangeable in this regard. Overproduction of DbpA also allowed the mutant to disseminate to some but not all distal tissues slightly slower than the control, but the mutant with DbpB overproduction showed severely impaired dissemination to all tissues that were analyzed. The mutant with DbpA overproduction colonized all tissues, albeit generating bacterial loads significantly lower than the control in heart and joint, while the mutant overproducing DbpB remained severely defective in heart colonization and registered bacterial loads substantially lower than the control in joint. Taken together, the study indicated that DbpA and DbpB play a similar role in contribution to infectivity as measured by ID50 value but contribute differently to dissemination and tissue colonization

Mercury DPM: fast, flexible particle simulations in complex geometries part II: applications

MercuryDPM is a particle-simulation software developed open-source by a global network of researchers. It was designed ​ab initio to simulate realistic geometries and materials, thus it contains several unique features not found in any other particle simulation software. These features have been discussed in a companion paper published in the DEM7 conference proceedings; here we present several challenging setups implemented in MercuryDPM ​ . Via these setups, we demonstrate the unique capability of the code to simulate and analyse highly complex geotechnical and industrial applications.These tups implemented include complex geometries such as (i) a screw conveyor, (ii) steady-state inflow conditions for chute flows, (iii) a confined conveyor belt to simulate a steady-state breaking wave, and(iii)aquasi-2D cylindrical slice to efficiently study shear flows.​MercuryDPM is also parallel, which we showcase via a multi-million particle simulations of a rotating drum. We further demonstrate how to simulate complex particle interactions, including: (i)deformable, charged clay particles; and (ii) liquid bridges and liquid migration in wet particulates, (iii) non-spherical particles implemented via superquadrics. Finally, we show how to analyse and complex systems using the unique micro-macro mapping (coarse-graining) tool MercuryCG

The PE-PPE Domain in Mycobacterium Reveals a Serine α/β Hydrolase Fold and Function: An In-Silico Analysis

The PE and PPE proteins first reported in the genome sequence of Mycobacterium tuberculosis strain H37Rv are now identified in all mycobacterial species. The PE-PPE domain (Pfam ID: PF08237) is a 225 amino acid residue conserved region located towards the C-terminus of some PE and PPE proteins and hypothetical proteins. Our in-silico sequence analysis revealed that this domain is present in all Mycobacteria, some Rhodococcus and Nocardia farcinica genomes. This domain comprises a pentapeptide sequence motif GxSxG/S at the N-terminus and conserved amino acid residues Ser, Asp and His that constitute a catalytic triad characteristic of lipase, esterase and cutinase activity. The fold prediction and comparative modeling of the 3-D structure of the PE-PPE domain revealed a “serine α/β hydrolase” structure with a central β-sheet flanked by α-helices on either side. The structure comprises a lid insertion with a closed structure conformation and has a solvent inaccessible active site. The oxyanion hole that stabilizes the negative charge on the tetrahedral intermediate has been identified. Our findings add to the growing list of serine hydrolases in mycobacterium, which are essential for the maintenance of their impermeable cell wall and virulence. These results provide the directions for the design of experiments to establish the function of PE and PPE proteins

Coupled down-regulation of mTOR and telomerase activity during fluorouracil-induced apoptosis of hepatocarcinoma Cells

<p>Abstract</p> <p>Background</p> <p>Hepatocellular carcinoma (HCC) is the most invasive and frequently diagnosed malignancy and the second leading cause of cancer death in many regions of Asia. The PI3K/Akt/mTOR signal pathway is involved in multiple cellular functions including proliferation, differentiation, tumorigenesis, and apoptosis. Up-regulation of telomerase activity is thought to be a critical step leading to cell transformation.</p> <p>Methods</p> <p>This study investigated changes in mTOR pathway and telomerase activity in hepatocarcinoma cell line SMMC-7721 treated with chemotherapeutic agent 5-fluorouracil (5-Fu). We detected apoptosis of hepatocarcinoma cells by TUNEL assay. Telomerase activity, hTERT transcription level and p- p70 S6k was demonstrated by the telomeric repeat amplification protocol and silver staining assay, Dual-Luciferase Reporter Assay and Western blot analysis respectively.</p> <p>Results</p> <p>Treating SMMC-7721 cells with 5-Fu leads to apoptosis of the cells, and reduction in telomerase activity, as well as a dramatic reduction in the activated form of p70 S6 kinase, a mTOR substrate. The 5-Fu treatment nearly abolishes transcription of hTERT (the major component of telomerase) mRNA. Treating SMMC-7721 cells with Rapamycin, a specific mTOR inhibitor, significantly reduce hTERT protein level but did not affect hTERT transcription. 5-Fu and rapamycin were synergistic in regards to down-regulation of telomerase activity in hepatocarcinoma cells.</p> <p>Conclusion</p> <p>These results suggest that chemotherapeutic agent 5-Fu may down-regulate telomerase activity at both transcriptional level and PI3K/Akt/mTOR pathway-dependent post-transcriptional level to facilitate hepatocellular carcinoma cell apoptosis.</p